Challenges
Datasets
Workspaces
Papers
Discussions
Leaderboard
Log inSign up
Challenges
Datasets
Workspaces
Papers
Discussions
Leaderboard
Blog
Job Board
Q3AS

© 2026 Aqora Quantum S.A.S.

TermsPrivacyLegal Notice

arXiv:cond-mat/9702100 · Physical review. B, Condensed matter

Quasiparticle photoemission intensity in doped two-dimensional quantum antiferromagnets

F. Lema, Armando A. Aligia

Published Jun 1, 1997• 20 citations
arXivHTMLPDF

Abstract

Using the self-consistent Born approximation, and the corresponding wave function of the magnetic polaron, we calculate the quasiparticle weight corresponding to destruction of a real electron (in contrast to creation of a spinless holon), as a function of wave vector for one hole in a generalized t-J model and the strong-coupling limit of a generalized Hubbard model. The results are in excellent agreement with those obtained by exact diagonalization of a sufficiently large cluster. Only the Hubbard weight compares very well with photoemission measurements in ${\mathrm{Sr}}_{2}$${\mathrm{CuO}}_{2}$${\mathrm{Cl}}_{2}$.

DOI
10.1103/physrevb.55.14092

Related papers

Spin polarons in the t - J model

Gerardo Martı́nez, Peter Horsch

The motion of a single hole in a two-dimensional Heisenberg antiferromagnet (hAF) is studied in a representation where holes are described as spinless fermions (holons) and spins as normal bosons. Assuming long-range AF order the spin dynamics is treated in linear spin-wave theory. The formulation highlights the close relation with the conventional polaron problem. The holon Green's function is calculated self-consistently within the Born approximation using finite-cluster geometries for the numerical solution. As a remarkable result we find close agreement with the spectral function A(k,\ensuremath{\omega}) of a hole calculated by exact diagonalization methods. A(k,\ensuremath{\omega}) is characterized by a narrow quasiparticle (QP) peak at the low-energy side of the spectrum, which is well separated from the incoherent part for large enough J values. A complete characterization of our solution is given, including the spectral weight, the dispersion relation, and effective masses of the QP state. A finite-size-scaling study gives a nonvanishing spectral weight of the QP in the thermodynamic limit for values J/t typical for copper oxide superconductors. Our calculations indicate that the self-consistent Born approximation is a valuable scheme for characterizing the dynamics of a hole in the t-J model, even in the strong-coupling regime.

Physical review. B, Condensed matter•Jul 1, 1991•498 citations

A single hole in a quantum antiferromagnet: selfconsistent Green’s function approach

Gerardo Martı́nez, Peter Horsch

We solved numerically the integral equation for the selfenergy which describes the motion of a single hole in a two-dimensional quantum antiferromagnet (AF) within the selfconsistent Born approximation. This formulation stresses the similarity of the AF-spin polaron with the standard polaron problem. We confine our calculation to finite cluster geometries and compare with results from previous exact diagonalization studies. The spectral function is characterized by a narrow quasiparticle (qp) peak at the low energy side of the spectra, which appears to be well separated from the incoherent band part for large enough J values. For small J we find a reduced width of ~7t for the incoherent band. The bottom of the coherent qp band always occurs at (±π/2, ±π/2). Its bandwidth initially increases with J until J≃t and then decreases as 2t2/J. A complete characterization of our solution is given, including the dispersion relation and effective masses of this quasiparticle. The comparison with exact diagonalization studies for a 4×4 cluster is remarkably good. From our results we see that a lattice of 16×16 sites describes adequately the thermodynamic limit. We conclude that the simple Born approximation is a valuable scheme to characterize the dynamics of one hole in the t-J model. both in the perturbative and the strong coupling regimes.

International Journal of Modern Physics B•Jan 1, 1991•12 citations

Photoemission spectra of a two-dimensional S=1/2 quantum antiferromagnet in magnetic fields: a theoretical study

Wei‐Guo Yin, W. N. Mei

We calculate the angular resolved photoemission spectra (ARPES) of a spin-1/2 Heisenberg antiferromagnet as a function of magnetic fields using both the exact diagonalization method and self-consistent Born approximation. Below the saturation field $B_C$, strong scattering between spin waves and a hole, created by photoemission of an electron, significantly narrows the quasiparticle band that is characterized by the lowering of the quasiparticle energy at $(π,π)$ with increasing field. Accordingly, in ARPES the quasiparticle peak gets shaper near $(π,π)$ and broader elsewhere. Furthermore, we observe that an anomalous extended van Hove region (EVHR) around $(π,π)$ appears in a half saturation field, while EVHRs around $(π,0)$ and $(0,π)$ in zero field gradually disappear with increasing field.

arXiv:cond-mat/0305174•May 8, 2003•0 citations

Spin polarons in thet-Jmodel: Shape and backflow

A. Ramšak, Peter Horsch

The self-consistent Born approximation for the self-energy and the wave function of a single hole moving in a two-dimensional quantum antiferromagnet is used to calculate various spin-correlation functions that characterize the perturbation induced by the hole. The results for these correlation functions agree with the available small-cluster calculations. The hole-spin correlation functions decay asymptotically with the distance from the hole as a power law and exhibit a dipolar distortion of the antiferromagnet. The quasiparticle spectral weight remains finite.

Physical review. B, Condensed matter•Oct 1, 1993•52 citations

Angle-resolved Cu and O photoemission intensities in CuO2 planes

J. Eroles, C. D. Batista, Armando A. Aligia

Using a mapping from the three-band extended Hubbard model for cuprate superconductors into a generalized $t\ensuremath{-}J$ model, and exact diagonalization of the latter in a $4\ifmmode\times\else\texttimes\fi{}4$ cluster, we determine the quasiparticle weight for destruction of Cu or O electrons with definite wave vector k. We also derive an approximate but accurate analytical expression which relates the O intensity with the quasiparticle weight in the generalized $t\ensuremath{-}J$ model. The k dependence of Cu and O intensities is markedly different. In particular the O intensity vanishes for $k=(0,0).$ Our results are relevant for the interpretation of angle-resolved photoemission experiments.

arXiv:cond-mat/9812325•Physical review. B, Condensed matter•Jun 1, 1999•12 citations

Spatial structure of spin polarons in the t−J model

A. Ramšak, Peter Horsch

The deformation of the quantum N\'eel state induced by a spin polaron is analyzed in a slave fermion approach. Our method is based on the self-consistent Born approximation for the Green's function and wave function for the quasiparticle. The results of various spin-correlation functions relative to the position of the moving hole are discussed and shown to agree with those available from small cluster calculations. Antiferromagnetic correlations in the direct neighborhood of the hole are reduced, but they remain antiferromagnetic even for $J$ as small as $0.1t$. These correlation functions exhibit dipolar distortions in the spin structure, which sensitively depend on the momentum of the quasiparticle. Their asymptotic decay with the distance from the hole is governed by power laws, yet the spectral weight of the quasiparticles does not vanish.

arXiv:cond-mat/9712119•Physical review. B, Condensed matter•Feb 15, 1998•43 citations
Using the self-consistent Born approximation, and the corresponding wave function of the magnetic polaron, we calculate the quasiparticle weight corresponding to destruction of a real electron (in contrast to creation of a spinless holon), as a function of wave vector for one hole in a generalized t-J model and the strong-coupling limit of a generalized Hubbard model. The results are in excellent agreement with those obtained by exact diagonalization of a sufficiently large cluster. Only the Hubbard weight compares very well with photoemission measurements in {\mathrm{Sr}}_{2}$${\mathrm{CuO}}_{2}$${\mathrm{Cl}}_{2}.
The motion of a single hole in a two-dimensional Heisenberg antiferromagnet (hAF) is studied in a representation where holes are described as spinless fermions (holons) and spins as normal bosons. Assuming long-range AF order the spin dynamics is treated in linear spin-wave theory. The formulation highlights the close relation with the conventional polaron problem. The holon Green's function is calculated self-consistently within the Born approximation using finite-cluster geometries for the numerical solution. As a remarkable result we find close agreement with the spectral function A(k,\ensuremath{\omega}) of a hole calculated by exact diagonalization methods. A(k,\ensuremath{\omega}) is characterized by a narrow quasiparticle (QP) peak at the low-energy side of the spectrum, which is well separated from the incoherent part for large enough J values. A complete characterization of our solution is given, including the spectral weight, the dispersion relation, and effective masses of the QP state. A finite-size-scaling study gives a nonvanishing spectral weight of the QP in the thermodynamic limit for values J/t typical for copper oxide superconductors. Our calculations indicate that the self-consistent Born approximation is a valuable scheme for characterizing the dynamics of a hole in the t-J model, even in the strong-coupling regime.
We solved numerically the integral equation for the selfenergy which describes the motion of a single hole in a two-dimensional quantum antiferromagnet (AF) within the selfconsistent Born approximation. This formulation stresses the similarity of the AF-spin polaron with the standard polaron problem. We confine our calculation to finite cluster geometries and compare with results from previous exact diagonalization studies. The spectral function is characterized by a narrow quasiparticle (qp) peak at the low energy side of the spectra, which appears to be well separated from the incoherent band part for large enough J values. For small J we find a reduced width of ~7t for the incoherent band. The bottom of the coherent qp band always occurs at (±π/2, ±π/2). Its bandwidth initially increases with J until J≃t and then decreases as 2t2/J. A complete characterization of our solution is given, including the dispersion relation and effective masses of this quasiparticle. The comparison with exact diagonalization studies for a 4×4 cluster is remarkably good. From our results we see that a lattice of 16×16 sites describes adequately the thermodynamic limit. We conclude that the simple Born approximation is a valuable scheme to characterize the dynamics of one hole in the t-J model. both in the perturbative and the strong coupling regimes.
We calculate the angular resolved photoemission spectra (ARPES) of a spin-1/2 Heisenberg antiferromagnet as a function of magnetic fields using both the exact diagonalization method and self-consistent Born approximation. Below the saturation field BCB_CBC​, strong scattering between spin waves and a hole, created by photoemission of an electron, significantly narrows the quasiparticle band that is characterized by the lowering of the quasiparticle energy at (π,π)(π,π)(π,π) with increasing field. Accordingly, in ARPES the quasiparticle peak gets shaper near (π,π)(π,π)(π,π) and broader elsewhere. Furthermore, we observe that an anomalous extended van Hove region (EVHR) around (π,π)(π,π)(π,π) appears in a half saturation field, while EVHRs around (π,0)(π,0)(π,0) and (0,π)(0,π)(0,π) in zero field gradually disappear with increasing field.
The self-consistent Born approximation for the self-energy and the wave function of a single hole moving in a two-dimensional quantum antiferromagnet is used to calculate various spin-correlation functions that characterize the perturbation induced by the hole. The results for these correlation functions agree with the available small-cluster calculations. The hole-spin correlation functions decay asymptotically with the distance from the hole as a power law and exhibit a dipolar distortion of the antiferromagnet. The quasiparticle spectral weight remains finite.
Using a mapping from the three-band extended Hubbard model for cuprate superconductors into a generalized $t\ensuremath{-}J$ model, and exact diagonalization of the latter in a $4\ifmmode\times\else\texttimes\fi{}4$ cluster, we determine the quasiparticle weight for destruction of Cu or O electrons with definite wave vector k. We also derive an approximate but accurate analytical expression which relates the O intensity with the quasiparticle weight in the generalized $t\ensuremath{-}J$ model. The k dependence of Cu and O intensities is markedly different. In particular the O intensity vanishes for k=(0,0).k=(0,0).k=(0,0). Our results are relevant for the interpretation of angle-resolved photoemission experiments.
The deformation of the quantum N\'eel state induced by a spin polaron is analyzed in a slave fermion approach. Our method is based on the self-consistent Born approximation for the Green's function and wave function for the quasiparticle. The results of various spin-correlation functions relative to the position of the moving hole are discussed and shown to agree with those available from small cluster calculations. Antiferromagnetic correlations in the direct neighborhood of the hole are reduced, but they remain antiferromagnetic even for JJJ as small as 0.1t0.1t0.1t. These correlation functions exhibit dipolar distortions in the spin structure, which sensitively depend on the momentum of the quasiparticle. Their asymptotic decay with the distance from the hole is governed by power laws, yet the spectral weight of the quasiparticles does not vanish.